Improvements are needed regarding protection against the erosion of shorelines. In many areas, soil conditions are such that shorelines or banks are susceptible to damage due to wave action and/or water wash induced by marine traffic, storms, flash floods and the like.
As an example of the erosion which can occur along a waterway and the problems associated therewith, consider the Mississippi River Gulf Outlet (the “MRGO”) which runs through coastal marsh of southeast Louisiana. Originally, the MRGO was conceived as a shortcut to the Port of New Orleans from the Gulf of Mexico avoiding the serpentine Mississippi River. There, the MRGO was created by dredging a channel through the mud, muck, marsh and wetlands of southeastern Louisiana. When originally completed, in the early 1960's, the MRGO was approximately 36-38 feet deep, and between 500 to 600 feet wide. Since then, the sidewalls and banks of the MRGO have been subjected to erosion due to wave action from marine vessels, as well as from waves induced via wind action, including tropical storms and hurricanes which periodically slam into the coast of Louisiana. As a result of such erosion of its sidewalls and banks, the average width of the MRGO by 2005 had expanded to about 2,000 feet, i.e., about three to four times its original width.
As the width of the MRGO grew, the adjacent coastline of Louisiana lost the benefit of the soil and vegetation which used to be present there and which served as a buffer to dampen the storm surge and winds which accompany tropical storms and hurricanes. The greatly expanded width of the MRGO, caused by the erosion of its sidewalls and banks, contributed to the devastation of the City of New Orleans and the surrounding area which was wrought by Hurricane Katrina in 2005. The hurricane's wind created a catastrophic storm surge of water that raced unimpeded up the hugely-expanded MRGO and into the city, resulting in over one thousand deaths and billions of dollars in property damage.
A similar problem exists where the shoreline of an open body of water, such as a lake, is subject to wave wash due to marine vessels and/or wind-induced wave action. The erosion of such shoreline is particularly detrimental when it occurs on barrier islands which otherwise serve to protect the adjacent mainland from storms. Such erosion also damages the delicate ecosystem and habitat of plants, animals and marine life living in the area.
A similar problem exists along the banks of fresh-water streams which are subject to erosion due to water wash associated with flash floods, as for example after a torrential rain.
To prevent such problems, various embodiments can provide cost-effective methods and apparatuses for protecting shorelines, sidewalls and banks against erosion due to wave action and/or water wash.
In various embodiments of the method and apparatus erosion preventing mats or blankets having oyster spat are placed to prevent or reduce erosion.
In prior art systems oyster spat and/or oyster larvae can spawn naturally so that as the reefs grow they can be harvested recreationally. As the oysters mature and spawn, larvae will adhere to blankets where the larvae can grow together tending to form a solid piece.
In naturally occurring prior art systems much of the oyster larvae released into the wild tends to float along water currents and not grow together to form a structure that resists erosion. Instead, these oyster larvae typically end up in commercially harvested oyster beds replenishing the natural supply of oysters harvested by oyster men.
Some erosion control systems have been patented. An example is U.S. Pat. No. 4,370,075 entitled Revetment Grids and Mats which is incorporated herein by reference.